Spray drawbar

Abstract

An extendible, collapsible spray drawbar device is disclosed comprising a triangular shaped frame structure adapted at the forward apex end for pivotal attachment to a prime mover and having wheels at the rear base end, transverse spray bar elements pivotally mounted to and extending from the base of the frame structure, wheels pivotally mounted to the outer end of the spray bar element, extension bar elements hingedly mounted to the outer end of the spray bar elements, and support elements pivotally mounted at one end to the transverse spray bar element and pivotally mounted at the other end about a horizontal and vertical axis to a brace member transversely extending across the triangular shaped frame structure. During the spraying operation, the transverse spray bar elements and the extension bar elements extend linearly from the base of the triangular shaped frame structure. For transportation, the support elements detach from the transverse brace and pivot toward the transverse spray bar element, the transverse spray bar elements and extension bar elements pivot rearwardly to a position approximately perpendicular to the base of the triangular shaped frame structure, and the wheels of the transverse spray bar element pivot 90° so as to be parallel to the wheels of the frame structure. The operational position of the spray drawbar provides spray bar reach across many rows while the transportation configuration provides an implement having a width generally less than the wheel span of a prime mover.

I claim: 
     
       1. A collapsible spray drawbar device, comprising, a frame means having a forward end and a rearward end, said forward end being adapted for pivotal connection to a prime mover,   first wheel means mounted to said frame means for engagement with the ground,   a pair of spray bar elements connected to said rearward end of said frame means at laterally spaced apart positions, each spray bar element connected for pivotal movement between an operating position wherein said spray bar element is extended transversely from said frame means and a transporting position wherein said spray bar element is extended approximately parallel to the longitudinal axis of said frame means,   a pair of second wheel means, each mounted to a respective one of said spray bar elements for engagement with the ground,   a pair of extension bar elements, each said extension bar element pivotally and detachably mounted to a respective one of said spray bar elements so as to be a linear extension of said spray bar elements,   each said extension bar element being mounted to said respective spray bar element by hinge means, said hinge means being a double-jointed hinge pivotally connected by shear pins so that said extension bar element pivots about said hinge means upon striking an immovable object, and   a pair of support bar elements, each said support bar element detachably and pivotally mounted to said frame means and to a respective one of said spray bar elements.   
     
     
       2. The device of claim 1 further comprising a stabilizer strap for connecting together said spray bar elements in the parallel transporting position with said stabilizer strap having opposite ends adapted for connection to said spray bar elements to provide stability during transportation. 
     
     
       3. The device of claim 1 wherein each said second wheel means comprises an axle, a ground wheel rotatably supported on said axle, means for supporting said axle on one of said spray bar elements for pivotal movement between an operating position directed generally parallel to said spray bar element and a transporting position directed generally perpendicular to said spray bar element and means for selectively fixing said axle in said operating and transporting positions. 
     
     
       4. The device of claim 3 wherein said means for supporting said axle includes an upright shaft rigidly connected to said axle and pivotally connected to one of said spray bar elements, said means for selectively fixing said axle including a plate securely attached to said shaft, said spray bar element having an aperture therein and said plate having spaced apart pin apertures positioned for registration with said spray bar aperture when said axle is in the operating and transporting positions therefor respectively, and a pin selectively received by a registered pair of said apertures to lock said axle in one of the operating and transporting positions therefor. 
     
     
       5. The device of claim 1 wherein said double-jointed hinge includes a first hinge plate securely attached to one of said spray bar elements, a second hinge plate securely attached to one of said extension bar elements and a pair of coacting shear pin receiving means on said first and second hinge plates at transversely spaced apart positions relative to the longitudinal axis of said spray bar element whereby said double-jointed hinge acts as a fracturable rigid connection when a pair of shear pins are received therein. 
     
     
       6. The device of claim 1 wherein each said support bar element comprises first and second support members having first and second ends, with said second end of said first support member detachably mounted to said first end of said second support member, said first end of said first support member pivotally mounted to said respective spray bar element, and said second end of said second support member pivotally attached to said frame means so as to pivot about a vertical and a horizontal axis, said second end of said first support member being detachably mounted to said first end of said second support member by a double-jointed hinge including shear pins for a fracturable rigid connection between said first and second support members.